1. Field of the Invention
The present invention generally relates to semiconductor equipment, and more particularly to a showerhead.
2. Description of Related Art
Semiconductor manufacturing equipments is commonly used in the production of semiconductor components. The semiconductor manufacturing equipment typically has a reaction chamber. The reaction gases which are required by the semiconductor manufacturing process can be provided into the reaction chamber by the showerhead of the reaction chamber. FIG. 1 shows a sectional view of a conventional showerhead 100. The conventional showerhead 100 includes a bottom portion 110, a plurality of gas tubes 120, a plate 130, and a top portion 140. Moreover, the conventional showerhead 100 includes a first space 191 and a second space 192, wherein the fluid which flows into the second space 192 can flow into the inside of the reaction chamber. On the other hand, the fluid which flows into the first space 191 will not flow into the inside of the reaction chamber. Therefore, cooling fluid, such as water, can flow into the first space 191 for cooling the conventional showerhead 100.
FIGS. 2A-2F show the making steps of the conventional showerhead 100 shown in FIG. 1. Referring to FIGS. 2A-2C, a bottom portion 110 and a plurality of gas tubes 120 are provided, wherein the bottom portion 110 has a plurality of openings. Then, the gas tubes 120 are inserted into the openings of the bottom portion 110. After that, a soldering process, such as a high temperature soldering process (hard soldering or brazing), is performed for fixing the gas tubes 120 on the openings of the bottom portion 110 and sealing the clearances between the gas tubes 120 and the openings. In the real case, the number of the gas tubes 120 can be thousands. Therefore, the step of inserting the gas tubes 120 into the openings of the bottom portion 110 may cost a long period of time. The quality of the conventional showerhead 100 is affected by the sealing performance of sealing the clearances between the gas tubes 120 and the openings of the bottom portion 110.
Referring to FIGS. 2D-2F, a plate 130 is provided, wherein the plate 130 has a plurality of openings. Then, the gas tubes 120 are inserted into the openings of the plate 130. After that, a soldering process, such as a high temperature soldering process (hard soldering or brazing), is performed for fixing the gas tubes 120 on the openings of the plate 130 and sealing the clearances between the gas tubes 120 and the openings of the plate 130. Finally, the top portion 140 is provided and assembled to the bottom portion 110 so as to finish the making steps of the conventional showerhead 100.
By the needs of the semiconductor process, the conventional showerhead 100 disposed within the reaction chamber has to bear high temperature and corrosion caused by reaction gases, such that the life-time of the conventional showerhead 100 is decreased. For example, high temperature, thermal cycling, and corrosion caused by reaction gases may damage the soldering portions for sealing the clearances between the gas tubes 120 and the openings of the bottom portion 110. The cooling fluid within the first space 191 may leak into the inside of the reaction chamber. Thus, the process yields are affected by the cooling fluid.
For the reason that there are some disadvantages of the prior art mentioned above, there is a need existed to propose a novel showerhead. The showerhead has better ability for bearing high temperature, thermal cycling, and corrosion caused by reaction gases. The showerhead has longer life-time, and the cooling fluid will not leak into the inside of the reaction chamber and affect the process yields.